Multi cell tube and manufacturing method

ABSTRACT

A method of manufacturing a multi-cell tube having two or more cells, which are repeatedly formed in longitudinal and circumferential directions of the tube in such a manner that fluid can be separately or simultaneously let into and/or out of the respective cells. The multi-cell tube comprises a cell unit including a plurality of cells arranged in one direction of the tube and have corresponding inlets in a direction intersecting with the direction in which the cells are arranged; a supply tube unit which has an opening/closing valve at any one side end thereof and communicates with the inlets of all the cells in a state where the supply tube unit is close to the cells; and an operating tube unit, made of inflatable material (e.g. rubber, plastics or the like), which is installed within the supply tube unit, and has an opening/closing valve at any one side end thereof.

TECHNICAL FIELD

The present invention relates to a multi-cell tube capable ofsimultaneously opening and closing a tube having a plurality of separatecells and a method for efficiently manufacturing the multi-cell tube.More specifically, the present invention is characterized in that aplurality of separate cells can be simultaneously filled with fluid andthe respective cells filled with the fluid are formed to be individuallyairtight when they are successively and repeatedly formed in alongitudinal direction of a tube, and that even though the fluid leaksout from any one of the cells due to a burst or breakage thereof, theother cells can be kept airtight.

BACKGROUND ART

In general, various kinds of tubes for accommodating gas or liquidtherein are typically formed with only one cell. If necessary, aplurality of cells may be formed in the tube by dividing the tube intothe multiple cells.

In all cases, the single cell should have at least one inlet (or inletand outlet). Further, if the single tube is divided into the multiplecells, it is common that each cell is constructed to have one inletbelonging thereto.

For example, a bolster constructed to accommodate air therein can bemanufactured such that an entire tube T of the bolster is formed with asingle cell as shown in FIG. 17 or is divided into a plurality of cellsas shown in FIG. 18. At this time, it is apparent that a single airinlet V is formed in the single-cell tube while each cell of themulti-cell tube has a single air inlet V belonging thereto.

In use, in a case where the entire tube T of the bolster is formed withonly one cell as shown in FIG. 17, it is easy to let the air into or outof the tube. However, when a user rests his/her head on the bolster, airresiding in a portion of the tube pressed down by his/her head is movedto the other portions of the tube. Thus, there is a problem in that thebolster does not fulfill its own proper function. In particular, if anyportion of the tube bursts open, whole air in the tube leaks out, andthus, an inherent function of the bolster is completely lost.

In addition, in a case where the tube T is formed with the plurality ofcells as shown in FIG. 18, it is inconvenient in that the air should belet into and out of the respective cells one by one. However, when theuser rests his/her head on the bolster, the air residing in the portionof the tube pressed down by his/her head is moved to the other portionsof the tube. Thus, there is convenience of use in that the head is notrocked. Furthermore, even though any portion of the tube bursts open,all the whole air in the tube does not fully leak out, and thus, thebolster does not completely lose its own inherent function.

Similarly, the above principle is also applied to a tank other than thetube.

For instance, in a case where an oil tanker is formed with a tank havinga single cell for accommodating oil therein, it is very convenient tolet the oil into and out of the tank, but the whole quantity of the oilwithin the tank inevitably leaks out when the oil begins to leak out inan emergency. Alternatively, in a case where the tank of the oil tankeris formed with a plurality of divided cells, the other cells are keptairtight even though any one cell is broken. Thus, a relatively smallamount of oil can leak out from the tank, but it is very inconvenient tolet the oil into and out of the tank.

DISCLOSURE OF INVENTION

Therefore, the present invention is conceived to solve the problems inthe prior art. A primary object of the present invention is tomanufacture a tube having two or more cells, which are repeatedly formedin longitudinal and circumferential directions of the tube, so thatfluid can be separately or simultaneously let into and/or out of therespective cells and the respective cells can be individually keptairtight.

Further, another object of the present invention is to efficientlymanufacture a tube in which a plurality of cells are successively andrepeatedly formed in longitudinal and circumferential directions of thetube so that the productivity thereof can be improved.

According to an aspect of the present invention for achieving the aboveobjects, there is provided a multi-cell tube, comprising: a cell unitincluding a plurality of cells which are arranged in a longitudinaldirection of the tube and have corresponding inlets formed in adirection intersecting with the direction in which the cells arearranged; a supply tube unit which has an opening/closing valve at anyone side end thereof and communicates with the inlets of all the cellsin a state where the supply tube unit is close to the cells; and anoperating tube unit which is installed within the supply tube unit, ispositioned in vicinity of the inlets of the cells, and has anopening/closing valve at any one side end thereof.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a sectional view showing the basic constitution of amulti-cell tube according to the present invention (in a state wherefluid can be injected into cells of the tube).

FIG. 2 is a sectional view showing the basic constitution of themulti-cell tube according to the present invention (in a state where thecells of the tube can be hermetically sealed).

FIG. 3 is a front view showing the constitution of a multi-cell tubeaccording to another preferred embodiment of the present invention.

FIG. 4 is a perspective view showing the constitution of the multi-celltube according to the preferred embodiment of the present invention.

FIG. 5 is a sectional view taken along line A—A of FIG. 3.

FIG. 6 is a sectional view taken along line B—B of FIG. 3.

FIG. 7 is a view showing a state where the multi-cell tube shown in FIG.5 is operated.

FIG. 8 is a sectional view illustrating a first step of a method formanufacturing a multi-cell tube according to the present invention.

FIG. 9 is a sectional view illustrating a second step of the method formanufacturing the multi-cell tube according to the present invention.

FIG. 10 is a perspective view illustrating the second step of the methodfor manufacturing the multi-cell tube according to the presentinvention.

FIG. 11 is a sectional view illustrating a third step of the method formanufacturing the multi-cell tube according to the present invention.

FIG. 12 is a plan view illustrating the third step of the method formanufacturing the multi-cell tube according to the present invention.

FIG. 13 is a perspective view illustrating a fourth step of the methodfor manufacturing the multi-cell tube according to the presentinvention.

FIG. 14 is a perspective view illustrating a fifth step of the methodfor manufacturing the multi-cell tube according to the presentinvention.

FIG. 15 is a sectional view showing the constitution of a multi-celltube according to a further preferred embodiment of the presentinvention.

FIG. 16 is a sectional view showing the constitution of a multi-celltube according to a still further preferred embodiment of the presentinvention.

FIG. 17 is an exemplary view of a general tube according to a prior art.

FIG. 18 is an exemplary view of a multi-cell tube according to the priorart.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, preferred embodiments of a multi-cell tube according to thepresent invention will be described in detail with reference to theaccompanying drawings.

Embodiment 1

FIG. 1 is a sectional view showing the constitution of a multi-cell tubeaccording to a basic embodiment of the present invention, and FIG. 2 isa sectional view showing a state where the multi-cell tube of FIG. 1 isoperated.

The multi-cell tube is mainly divided into a cell unit 10, a supply tubeunit 20, and an operating tube unit 30.

As shown in the figures, the cell unit 10 is composed of a plurality ofcells 11 which are arranged in a direction of the tube, and each of thecells 11 has an inlet 12 formed in a direction intersecting with thedirection in which the cells are arranged.

The supply tube unit 20 is formed to extend long in the same directionas the arrangement of the cells 11, communicates with the inlets 12 ofall the cells in a state where it is close to the cells, and has anopening/closing valve 21 at any one side end thereof.

The operating tube unit 30 is disposed adjacent to the inlets 12 of thecells 11 in a state where it is installed within the supply tube unit20, and also has an opening/closing valve 31 at any one side endthereof.

The operation of the multi-cell tube of the present inventionconstructed as such is performed by first supplying a fluid to be filledinto the cells to the supply tube unit 20 through the opening/closingvalve 21 thereof.

The fluid filled into the supply tube unit 20 is introduced into thecells 11 through the inlets 12 of the cells 11. After the cells 11 havebeen completely filled with the fluid, another fluid (e.g., air) capableof inflating the operating tube unit 30 is introduced into the operatingtube unit 30 through the opening/closing valve 31 thereof.

Thereafter, the fluid filled into the operating tube unit 30 causes theoperating tube unit 30 to be inflated as shown in FIG. 2. Thus, theoperating tube unit 30 installed within the supply tube unit 20 canclose the cells 11 since the inflated portions thereof located adjacentto the inlets 12 come into uniform and close contact with the inlets 12.

At this time, assuming that pressure within the operating tube unit 30and the cells 11 is P2 and P1, respectively, a pressure condition ofP2>P1 must be maintained. However, there is no great problem in that thepressure condition can be maintained by simply closing theopening/closing valve 31 after sufficiently supplying the fluid into theoperating tube unit 30 so as to increase the pressure therein.

It is expected that the multi-cell tube of the present invention can bepractically employed in a cargo tank of an oil tanker, a ship, a fueltank of an airplane, etc.

That is, a space within the oil tanker for accommodating the oil thereinis divided into the plurality of cells, and the respective cells arefilled with the oil. At this time, the cells can be simultaneouslyfilled with the oil and simultaneously opened and closed using thesupply tube unit and the operating tube unit as described above.

According to such a constitution of the present invention, although themulti-cell tube has the plurality of cells, it is not necessary toprovide one valve to every cell. Further, the multi-cell tube of thepresent invention is convenient in that when the same kind of oil isfilled or loaded into the cells, it can be simultaneously let into orout of the cells.

In particular, according to the constitution of the present invention,the respective cells can be individually kept airtight. Thus, eventhough any one of the cells may be broken due to shipwreck, it does nothave any influence on the other adjacent cells in view of their airtightcharacteristics. Consequently, there is an advantage in thatenvironmental pollution, casualties, and financial loss are reducedsince the oil leakage can be minimized.

Embodiment 2

FIG. 3 is a front view showing the constitution of a multi-cell tubeaccording to another preferred embodiment of the present invention, andFIG. 4 is a perspective view of the multi-cell tube shown in FIG. 3.

As shown in the figures, the multi-cell tube according to thisembodiment of the present invention is mainly divided into the cell unit10, the supply tube unit 20, and the operating tube unit 30 in the samemanner as the previous embodiment. This embodiment is characterized inthat all the units are integrally formed from a hollow cylindrical sheetof material 1, i.e. a hollow cylindrical sheet of synthetic resinmaterial (e.g., PE, PP or the like, hereinafter referred to as“synthetic resin material”) in order to manufacture the units in a mostefficient manner.

The supply tube unit 20 and the cell unit 10 are separated from eachother by division line sections 13 which are formed by fusion welding ofintermediate portions of the hollow cylindrical material 1. Further, theoperating tube unit 30, which is formed by inwardly folding a portion ofthe cylindrical material 1 and then inserting the folded portion intothe cylindrical material 1, is provided in the supply tube unit 20. Thatis, the operating tube unit 30 is finally formed by fusion welding of anouter end of the inwardly folded portion in a state where the inwardlyfolded portion is overlapped with an inner side of the remaining portionof the cylindrical material.

At this time, it is essential that a plurality of inlets 12 should beformed between the division line sections 13 so that the supply tubeunit 20 can communicate with the respective cells 11 through the inlets12. Furthermore, the division line sections 13 are preferably formed insuch a manner that an extension portion 32 corresponding to a part ofthe inwardly folded portion protrudes into the cell unit 10 so that theoperating tube unit 30 can effectively close up the inlets wheninflated.

In addition, the cell unit 10 is divided into the plurality of cells 11by repeatedly forming a plurality of partition line sections 14 withinranges of the division line sections 13.

The supply tube unit 20 and the operating tube unit 30 are provided withvalves 21, 31, respectively. Flat valves can be used as the valves 21,31.

The flat valve includes a valve plate a formed to prevent insidepressure from leaking out when a sheet of the synthetic resin material(e.g., elastic vinyl etc.) is folded into two to come into close surfacecontact with each other, and a straw b inserted into the valve plate forallowing the air to be let into and out of the units. The flat valve isbonded to the units by the fusion welding process so that inner andouter ends thereof are positioned inside and outside the units,respectively.

Hereinafter, a method of manufacturing the multi-cell tube according tothis embodiment of the present invention will be explained.

In order to manufacture the multi-cell tube of the present inventionusing a sheet of the cylindrical material 1 made of the synthetic resinmaterial, a material preparation process, a folding process, a dividingprocess, and a valve attachment process will be performed.

In the material preparation process, either a preformed cylindricalsynthetic resin material or a cylindrical synthetic resin material 1formed by bonding both ends thereof is prepared, as shown in FIG. 8.

At this time, it is apparent that width and length of the syntheticresin material are determined depending on the sizes and number of themulti-cell tubes which are intended to be manufactured.

In the folding process, the cylindrical synthetic resin materialobtained from the material preparation process is flatly folded. Then,as shown in FIG. 9, one side end (right portion in the figure) of thecylindrical material in a widthwise direction is inwardly folded andinserted into the remaining portion thereof so that a unit 40 fordefining a three-dimensional structure can be prepared beforehand.Further, the other side end (left portion in the figure) of thecylindrical material in the widthwise direction is also inwardly foldedand inserted into the remaining portion thereof so that portions to beformed into the supply tube unit 20 and the operating tube unit 30 arebeforehand prepared.

In the division process, the division line sections 13 and the partitionline sections 14 are formed in a state where the multi-cell tube isfolded as in the folding process.

That is, as shown in FIG. 11, both ends of the portions, which wasinwardly folded and inserted into the remaining portion thereof to beformed into the supply tube unit 20 and the operating tube unit 30, arebonded through the fusion welding process so that the supply tube unit20 and the operating tube unit 30 are completed.

Further, if such a division process is to be performed successively in adirection in which the cells are arranged, it is preferred that thedivision line sections 13 and the partition line sections 14 be formedsuccessively and repeatedly using a heating roller 50 as shown in FIG.12.

At this time, since portions which are not bonded, i.e. the inlets 12,should be formed between the division line sections 13, it is preferredthat the roller be manufactured so that each of the inlets 12 can beformed at a position corresponding to the center of a width of each cell11.

In the valve attachment process, after the cells 11 of the cell unit 10,the supply tube unit 20, and the operating tube unit 30 have been formedthrough the division process, the opening/closing valve 21 is attachedto the one side end of the supply tube unit 20 as shown in FIG. 13 whilethe opening/closing valve 31 is also attached to the one side end of theoperating tube unit 30 as shown in FIG. 14.

After the valve attachment process has been completed as such, thepredetermined fluid can be supplied into the supply tube unit 20 throughthe opening/closing valve 21 for use in the supply tube unit 20. Thefluid to be supplied is introduced into the respective cells 11 throughthe corresponding inlets 12 as shown in the left of FIG. 4.

After the supply of the fluid has been completed, another fluid isintroduced into the operating tube unit 30, which is in turn inflated.In particular, since the extension portion 32 of the operating tube unit30 protrudes into the cells 11, simultaneous inflation of the extensionportion 32 allows the inlets 12 to be closed up effectively andcompletely.

Consequently, since the pressure P2 within the operating tube unit 30and the extension portion 32 thereof protruding into each of the cells11 is greater than the pressure P1 within the cell 11, the fluidsupplied into every cell 11 does not leak out unless the inlets 12 areopened due to reduction of the fluid pressure within the operating tubeunit 30. Even though any one of the cells 11 bursts open in such anairtight state, the fluid cannot leak out from the other cells 11 sinceall the cells are individually kept airtight.

Embodiment 3

The present invention may be implemented to include a plurality of cellunits 10 at a single supply tube unit 20 in three, four or moredirections by improving the structure of Embodiment 2.

That is, as shown in FIGS. 15 and 16, the plurality of cell units 10 canbe simultaneously formed at an angular interval such as about 90 or 120degrees around the single supply tube unit 20 centrally positioned amongthe cell units.

A multi-cell tube according to this embodiment of the present inventionis also manufactured in the same manner as Embodiment 2, but should bemanufactured by successively performing an improved folding process offolding the single cylindrical material 1 to be formed into the units,and an improved division process of forming the division line sections13 and the partition line sections 14 belonging to the units.

Further, since the cell units 10, the supply tube unit 20 and theoperating tube unit 30 of the multi-cell tube of the present inventionare successively and repeatedly manufactured in a longitudinal directionof the cylindrical material 1, the multi-cell tube cut at desiredlengths can be individually used. And then, the multi-cell tube can becompleted by bonding thereto the opening/closing valve 21 for the supplytube unit 20 and the opening/closing valve 31 for the operating tubeunit 30.

As described in detail above, the multi-cell tube according to thepresent invention is constructed such that the respective cells areseparately formed and arranged, the fluid can be simultaneously let intoand out of the respective cells, and the respective cells can beindividually kept airtight. Therefore, even though any one of the cellsbursts open or is damaged, all the other cells can be kept airtight.

Accordingly, since the fluid leakage due to the probable damage to thecells can be restricted and minimized to the relevant cells, it cancontribute to the protection of environment. Further, the casualties canbe reduced when the multi-cell tube of the present invention is employedin water toys, rubber boats and the like. Furthermore, convenience oflife is improved since various kinds of chair cushions and airbeds/mattresses can be made using the multi-cell tube.

Reference Numerals for Designating Main Components in the Drawings

-   1: Material-   10: Cell portion-   11: Cell-   12: Inlet-   13: Division line section-   14: Partition line section-   20: Supply tube unit-   21: Opening/closing valve-   30: Operating tube unit-   31: Opening/closing valve-   32: Extension portion-   40: Portion for defining three-dimensional structure-   50: Roller

1. A method of manufacturing a multi-cell tube, comprising: a materialpreparation step of preparing a preformed cylindrical synthetic resinmaterial or a cylindrical synthetic resin material formed by bondingboth ends thereof; a folding step of preparing a portion (40) fordefining a three-dimensional structure by inwardly folding and insertingone side end of the cylindrical material into the remaining portionthereof after flatly folding the cylindrical synthetic resin materialprepared in the material preparation step, and preparing portions to beformed into the supply tube unit (20) and the operating tube unit (30)by inwardly folding and inserting the other side end of the cylindricalmaterial into the remaining portion thereof; a division step of formingdivision line sections having inlets along a direction in which thecells are arranged so that the supply tube unit and operating tube unitprepared in the folding step can be formed, and repeatedly formingpartition line sections along a direction intersecting with thedirection in which the cells are arranged; and a valve attachment stepof attaching opening/closing valves to one side ends of the supplyingtube unit and the operating tube unit prepared in the division step,respectively, and sealing opposite side ends of the units.
 2. The methodas claimed in claim 1, wherein in the division step, the division linesections and the partition line sections are formed by a fusion weldingmeans.
 3. The method as claimed in claim 2, the fusion welding meansincludes a fusion welding roller used for successively and repeatedlyforming the division line sections and the partition line sections inthe direction in which the cells are arranged.